1. Field of the Invention
The present invention relates generally to therapeutic devices for the treatment of localized injury or pain and specifically, to a microwave actuable heating pad which is malleable allowing the pad to molded about the localized area to be treated.
2. Description of the Prior Art
It is well known that, for a therapeutic effect, both human and animal muscle tissue should be heated in some circumstances and chilled in others. For instance, sprained or strained muscle tissues are generally chilled to reduce swelling and further damage. Small, specialized ice packs are known which are designed for application of cold to localized areas.
Similarly, a variety of devices are known in the prior art for applying heat to localized areas of pain. Such devices include hot water bottles, which are ordinarily made of flexible rubber, and which can also include insulated coverings for conserving heat when the hot water bottle is filled with hot water. For instance, see U.S. Pat. No. 2,072,564, issued Mar. 2, 1937, to May, entitled Hot Water Bottle Cover. Other heating devices include electric heating pads in which a plurality of resistive heating elements are electrically actuated to provide a source of heat for treating localized area of pain.
The prior art hot water bottle suffers from a variety of disadvantages. The device is cumbersome to use since it is necessary to fill the interior of the bottle with hot water from a tap. Even with an insulated covering, the device lacks the ability to retain a significant amount of heat for a prolonged period of time. The electric heating pad, while more efficient in operation and heat transfer ability, suffers from various limitations including the encumbrance which results from being attached to a power source by wires. Also, the electric pad can constitute a hazard from electrical voltage if used around water, such as in a bath area.
Another shortcoming of the prior art devices is that the heating device is not generally putty-like in nature and cannot be effectively molded about the body part to be treated, for instance the elbow or the knee area of the human body. U.S. Pat. Nos. 4,756,311 and 4,920,964 are related patents which both show thermal compresses which contain a cold pack gel material. The gel material is laminated by an envelope made of a film of synthetic resin. The gel pack is microwaved in order to actuate and heat the gel material but the sealed envelope is not moldable about a body part to the extent that a putty-like compound would be. U.S. Pat. No. 4,671,267 shows a body of gel which is encased within a heat permeable stretch fabric and applied to a body part. The reference also teaches applying the gel material directly to the injured skin to create a temporary skin with improved air permeability. The patent does not teach the inclusion of an electromagnetic absorptive agent to render the material microwaveable, however.
A need exists for an improved device and method for applying heat to localized areas of both human and animal bodies for relief of pain and for the prevention and/or treatment of injury.
A need also exists for such a device which is heat actuable without the presence of electric wires and which retains its heat transfer properties for a prolonged time period.
A need also exists for such a device which is putty-like in nature, allowing the device to be molded about the localized area to be treated in order to improve the therapeutic effect thereof.